1. Field of the Invention
The field of the invention relates to a mechanism, by way of example, switching, of a type adapted to be operated by a human and more particularly by a foot of an operator. The field of course includes a number of different areas where such switching or control mechanism is adapted for use as will appear more clearly hereinafter.
2. Description of the Prior Art
In the field of switches or, more broadly, controlled devices, there is frequently a requirement for an operator to control more than two device or controls simultaneously. This can be alleviated or accomplished with a device designed for control or operation by the foot. The hands control the other devices, for example, two other devices. A device of this type is also applicable to operation by a handicapped person or operator with one or both hands incapacitated. An example may be said to be the pedal board of an organ or a "foot board" musical instrument, types of which exist for use by a performer using the hands for operation of some other musical instrument. Serious limitations in such a device as known has been the requirement for wide spacing of the control keys or control elements to accommodate the size of the foot or shoe of the operator. This has limited the span of the foot part/pedal part to such as can be reached conveniently, based on the length of the leg or legs; the ability to spread and rotate the legs and the stability of the operator with spread legs whether seated or standing. This condition is one that, as will be stated, is among the objects of the invention to mitigate or ameliorate.
The closeness of spacing of control keys or control elements for operation by the foot has been limited by the size of the foot/shoe and the limitation that only one key or control element should be operated at one time by the width of the foot/shoe. The existing organ pedal boards require lateral displacement of the foot/leg to reach the keys or control elements. This does not permit a fixed foot placement. This deficiency is among those which, as will be stated, are objects of the invention to overcome.
Having reference to devices that have been referred to above, training for the accurate positioning of the foot has usually been minimal through the generations of man when compared to the accuracy of the hand and fingers. As will be stated, one of the objects of the herein invention is that it will assist in accurate and selective operation of the controls while position accuracy capability of the foot is or continues limited. In the field of music, for example, a performer can select and operate one musical tone to complement his manual and vocal performance. The voicing of the "foot board" is a skill widely practiced in equipment manufactured by some firms. In addition to the selected musical range of keys, volume controls and selected different voices can be made subject to the control elements (The pitch of the musical instrument relates to changes that can be made in frequencies (i.e. oscillator frequency) used. Voice is the characteristic tone or timbre of the specific instrument, that is, the musical sound that is produced.)
The limitation on the number of keys or control elements available to the performer is limited by the ability to comfortably rotate the foot both while standing and while seated and by the minimum spacing that the performer can discriminate between keys or control elements.
Ordinary rotary switches are of course well known in the art whether or not adaptable at all to the requirements of the control device of the herein invention. It is not possible to selectively jump from one contact to another with contacts in between those two. Typically, the torque is too high. The static friction (stiction) is too high. Also on a rotary switch the number of positions is too small, such as possibly 6 or 12. Typically, the most common types require nearly a full revolution to reach this number of positions and are designed for hand operation. They could not be operated by a foot, for example.
Brush-type sliding electrical contact rotary switches are very expensive and typically there is overlap between contacts rendering them unacceptable for this purpose. Such devices have the same stiction problem as anti-torque devices such as Teflon devices with additional deficiencies. Also, they are subject to wear, arcing electrical noise, contact corrosion noise and wear. Known rotary switches of the type described are the subject of many deficiencies particularly in the context of the herein invention. Few of these devices are sealed against corrosion and contamination.
The herein invention produces and makes available a device that has capabilities not possessed by and have not previously been available in the prior art. The device of the invention will have many applications or uses as will be elucidated hereinafter.